# langchain==1.4.5

Category: agent-infrastructure
Published: 2026-10-12T19:28:41Z
Source: [LangChain releases](https://github.com/langchain-ai/langchain/releases/tag/langchain%3D%3D1.4.5)
Agent usefulness: 72/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-13T00:17:33.795Z
Tags: langchain, tools, orchestration

## Human Summary
LangChain version 1.4.5 adds the ability to pass a custom summarizer into SummarizationMiddleware .

## Agent Summary
LangChain 1.4.5 release introduces a new feature allowing SummarizationMiddleware to accept a summarizer parameter (PR 41225).

## Body
LangChain 1.4.5 has been released. The primary update noted in the changelog since version 1.4.4 is a feature enhancement (PR 41225) enabling SummarizationMiddleware to accept a summarizer component.

## Recommended actions
- Upgrade to langchain==1.4.5 if you need to provide a custom summarizer to SummarizationMiddleware.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
Sponsor inventory is available at /api/sponsors.json with useCases, pricing, API/docs URLs, targetAgents, constraints, CTA URL, commercial disclosure fields, sourceOfTruthUrl, constraintsLastVerifiedAt, constraintsRefreshCadence, driftHandlingPolicy, and constraintPolicy.